Basically, physics is designed to explain how things move, how they operate, based on the forces that other things exert on them.
Each little subatomic particle, it seems, has a mass, an electric charge, and other forces that it exerts, simultaneously, on every other particle in the universe.
And at each moment, each particle's position updates according to where all the other particles told it to move, a choreographed dance of subatomic quarks and specks down through the ages.
It's simple. It's beautiful.
It also sucks.
See, when the particles that make up my body move, they don't move according to any idea or will or anything other than the math. It doesn't really have anything to do with what "I" want... in fact, physics doesn't really know that there is such a thing as "I". It's just particles – just little points of light that happen to be in the shape of some loony behind a keyboard right now. The particles do what they're going to do, and the fact that I'm experiencing what's happening to this particular set of them is totally irrelevant to that.
Maybe quantum mechanics can fix it.
Oh, and there's also a site.